不同轻基质配比对核桃楸容器苗根系形态和养分累积的影响

为探究不同轻基质组成和配比对核桃楸容器苗根系的影响,为核桃楸优质苗木培育提供依据,以当年生核桃楸幼苗为研究对象,选用泥炭土、蛭石、珍珠岩、废弃木耳菌棒和锯末进行不同比例组合,设置12种不同轻基质配比,比较不同处理下核桃楸幼苗根系发育和养分累积的差异。结果表明,S9(泥炭土︰珍珠岩︰木耳菌棒=3︰3︰4)处理下的土壤毛管持水量和田间持水量显著高于其余处理。分别在第60 d和第45 d时,苗高和地径表现出较高的变异。在生长结束时,S6(泥炭土︰:珍珠岩︰:木耳菌棒=5︰3︰2)、S7(泥炭土︰珍珠岩︰锯末=3︰3︰4)和S9处理下核桃楸苗木的苗高显著高于其他处理,分别比CK高58.94%、58.83%和54.28%。S9处理的比根长(SRL)、比根表面积(SRA)和平均直径(AD)最大,分别比CK高141.75%、88.22%和76.54%。S9和S7处理的根系生物量分别为6.22 g/株和5.06 g/株,显著高于CK。S9和S7处理的幼苗根系各养分浓度均显著高于CK。各处理间的幼苗根系的磷浓度均未达到显著水平。不同轻基质配比的土壤容重与根系形态学参数和养分浓度存在显著的负相关关系,核桃楸根系形态与根系养分浓度存在极显著的正相关关系。采用30%泥炭土+30%珍珠岩+40%木耳菌棒组成的轻基质配比最适合核桃楸当年生幼苗的根系生长和发育,能够有效地提高其根系养分吸收能力并积累更多的养分。

Effects of Different Light Substrate Composition on Root Morphology and Nutrient Accumulation of Juglans mandshurica Seedlings

The one-year old seedlings of Juglans mandshurica were selected as research objects,this study is to explore the effects of different light substrate composition and proportion on the root system of J.mandshurica seedlings,and then provide a basis for the cultivation of high-quality seedlings.Peat soil,vermiculite,perlite,waste fungus rod and sawdust were conducted to make twelve different proportions of light substrates composition.The objective is to compare the root development and nutrient accumulation of J.mandshurica seedlings under different treatments.The results showed that the capillary water holding capacity and field capacity of S9(peat soil︰perlite︰fungus rod=3︰3︰4)were significantly higher than other treatments.On the 60th and 45th day,the seedling height and ground diameter showed higher variation respectively.At the end of growth,seedling height of S6(peat soil︰perlite︰fungus rod=5︰3︰2),S7(peat soil︰perlite︰sawdust=3︰3︰4)and S9 treatment were significantly higher than other light substrates composition,which is 58.94%,58.83%and 54.28%significantly higher than CK,respectively.The specific root length(SRL),specific root surface area(SRA)and average diameter(AD)of S9 were highest and 141.75%,88.22%and 76.54%higher than CK,respectively.The root biomass of S9 and S7 treatments were 6.22 g/seedling and 5.06 g/seedling,respectively,which were significantly higher than CK.The root nutrient concentrations of S9 and S7 were significantly higher than CK.The phosphorus concentration in the roots of the seedlings in each treatment did not reach a significant level.There was a significant negative correlation among soil bulk density,root morphological parameters and nutrient concentrations in different light substrates composition.There was a significant positive correlation between root morphology and root nutrient concentration.The light substrates composition consisting of 30%peat soil,30%perlite and 40%fungus rod is most suitable for the root growth and development of the walnut seedlings,which could effectively improve the root nutrient absorption capacity and accumulate more nutrients.